Stop watching for API changes in WATCHLISTS

TBR=verwaest@chromium.org

Change-Id: If18d402f9b0b9c500307fd454eafe93de701599c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2141731Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67048}

WATCHLISTS

@@ -33,10 +33,6 @@
 
 {
   'WATCHLIST_DEFINITIONS': {
-    'api': {
-      'filepath': 'include/' \
-                  '|src/api\.(cc|h)$',
-    },
     'snapshot': {
       'filepath': 'src/snapshot/',
     },
@@ -94,9 +90,6 @@
   },
 
   'WATCHLISTS': {
-    'api': [
-      'yangguo+watch@chromium.org',
-    ],
     'csa': [
       'jgruber+watch@chromium.org',
     ],